The 1973 Pontiac Grand Am arrived at a moment when Pontiac was blending mid-size comfort, upscale trim, and more European-flavored road manners into an American performance-era package. That combination gives the car a distinct place among early 1970s Pontiacs, and tire choice plays a big role in preserving its stance and character. The 1973 Pontiac Grand Am uses a GR70-15 radial tire on a 15-inch rim, so the decision is less about sorting through multiple factory sizes and more about choosing the right presentation within that fitment. Available GR70-15 options lean toward period-style bias-look radial designs with either pin white stripe or raised white letter sidewalls. That makes appearance, wheel compatibility, and intended driving use especially important before making a final selection.
Which Tire Size Is Right for The 1973 Pontiac Grand Am
The 1973 Pontiac Grand Am uses one primary tire size: GR70-15. It is a radial fitment on a 15-inch rim, and the Grand Am Base uses that same size, so the main decision is not which size fits but which GR70-15 tire best matches the car's appearance, wheel setup, and road-use goals.
GR70-15 is an alphanumeric radial size in which the letter code identifies the tire's width class, the R denotes radial construction, the 70 indicates its profile family, and the 15 refers to the wheel diameter. On a 1973 Pontiac Grand Am, this size keeps the fitment centered on the car's original-era radial character rather than an earlier numeric or bias-ply format. Available choices include Goodyear offerings in series such as GM Custom Tread, Steelgard, and Custom Wide Tread, with both pin white stripe and raised white letter sidewall treatments. That makes GR70-15 a size where visual style and wheel-width compatibility matter just as much as simply matching the code.
Sub-model fitment is straightforward for the 1973 Pontiac Grand Am. The covered Grand Am Base uses the same GR70-15 radial size, so tire selection comes down to construction style, sidewall appearance, and wheel compatibility rather than sorting between different factory sizes.
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1973 Pontiac Grand Am Base
The 1973 Pontiac Grand Am Base uses the GR70-15 radial tire size on a 15-inch wheel. That keeps selection focused on choosing among period-style GR70-15 options, including different sidewall treatments and tire series, while confirming the car still has the correct wheel setup.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 1973 Pontiac Grand Am Tires for Sale
Available GR70-15 choices for the 1973 Pontiac Grand Am center on Goodyear bias-look radial designs in GM Custom Tread, Steelgard, and Custom Wide Tread series. The main points to compare are sidewall style, series appearance, and the wheel-width range each tire is intended to suit.
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Goodyear Tires
Goodyear GM Custom Tread Pin White Stripe | GR70-15
Owners of a 1973 Pontiac Grand Am usually want clarity on the GR70-15 fitment, 15-inch wheel compatibility, period-style sidewall choices, and what to inspect before putting a collector-era Pontiac back on the road.
Tire Size & Fitment
What tire size fits a 1973 Pontiac Grand Am?
The 1973 Pontiac Grand Am uses GR70-15 tires. That is the primary fitment for this model, and the Grand Am Base uses the same GR70-15 radial size, so there is no split between multiple original tire sizes within the covered sub-models.
The practical decision is choosing the right GR70-15 tire rather than sorting through several fitments. A buyer should still confirm that the car retains 15-inch wheels and has not been changed to a different wheel diameter, width, or stance, because aftermarket wheels and suspension changes can affect what works comfortably on the car.
What size rim does a 1973 Pontiac Grand Am use?
The 1973 Pontiac Grand Am uses a 15-inch rim with its GR70-15 tire size. The tire size itself ends in 15, and the available Grand Am products for this fitment are built for 15-inch wheels, which keeps the wheel diameter straightforward.
Rim diameter is only part of the check. Wheel width also matters when comparing available GR70-15 products, since some are intended for slightly different width ranges. Measuring the actual wheel on the car is worthwhile, especially on a restored or modified Grand Am where replacement wheels may not match the original setup exactly.
Does the 1973 Pontiac Grand Am Base use the same tire size?
Yes. The 1973 Pontiac Grand Am Base uses the same GR70-15 radial tire size as the core 1973 Pontiac Grand Am fitment. That means the sub-model does not introduce a separate tire-size question within the covered application.
That consistency makes shopping simpler, but it does not remove the need to check the car itself. A Grand Am Base with aftermarket wheels, changed ride height, or non-original wheel widths may need closer inspection before choosing among GR70-15 tires, particularly when comparing sidewall styles and bias-look radial constructions.
Choosing the Right Tire
What should I consider when choosing a GR70-15 tire for a 1973 Pontiac Grand Am?
Start with the correct size, which is GR70-15, then compare the tire's construction style, intended wheel-width compatibility, and overall appearance. For the 1973 Pontiac Grand Am, the available choices are bias-look radial designs, so the main differences come from series styling and how traditional or sporty the sidewall presentation looks.
It also helps to think about how the car will be used. A Grand Am aimed at restoration-oriented presentation may call for a different look than one built for regular weekend driving. Matching the tire to the actual wheel width on the car can prevent a good-looking GR70-15 choice from becoming a poor fit in practice.
What sidewall styles are available for 1973 Pontiac Grand Am tires?
GR70-15 tires for the 1973 Pontiac Grand Am are available with pin white stripe and RWL sidewall treatments. RWL refers to raised white letter styling, while pin white stripe offers a more restrained stripe appearance that suits many 1970s restoration and period-style themes.
The right choice depends largely on how the car is being presented. A buyer focused on a cleaner, more understated look may lean toward pin white stripe, while raised white letters create a stronger muscle-era visual statement. Since both styles exist in the correct size, sidewall appearance becomes a meaningful part of the decision.
What tire series are available for the 1973 Pontiac Grand Am?
The GR70-15 fitment for the 1973 Pontiac Grand Am is available in Goodyear series including GM Custom Tread, Steelgard, and Custom Wide Tread. Those series give the buyer several period-style presentations within the same basic size and radial format.
Series choice matters mostly for appearance and product character rather than changing the car's primary size requirement. Comparing the series alongside sidewall style and wheel-width specifications is the useful next step, especially if the goal is to match the tire's visual personality to the way the Grand Am is being restored or driven.
Restoration & Appearance
Which tire should I choose for a period-style 1973 Pontiac Grand Am?
A period-style 1973 Pontiac Grand Am tire choice starts with the correct GR70-15 size and then narrows to the visual treatment that best suits the car. The available options are bias-look radial designs, which can preserve a traditional 1970s-style presentation while staying within the Grand Am's radial fitment.
That means the decision is often about the look of the tire as much as the size itself. Comparing series names, sidewall treatments, and wheel-width requirements will usually be more helpful than simply picking the first GR70-15 available. When exact originality matters, marque-specific restoration references remain the best way to verify appearance details.
How does tire construction affect the appearance of a restored 1973 Pontiac Grand Am?
Tire construction changes more than ride feel; it also changes how a restored 1973 Pontiac Grand Am looks at a glance. In this fitment, the available GR70-15 choices are bias-look radial tires, which are designed to keep a traditional vintage appearance instead of looking like a modern replacement radial.
That makes construction part of the visual decision, not just a technical one. Sidewall styling such as pin white stripe or raised white letter treatment will shape the car's stance and personality even further. A buyer trying to maintain a strong early-1970s presentation should consider both the construction style and the sidewall design together.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1973 Pontiac Grand Am?
Yes. Even though the 1973 Pontiac Grand Am uses GR70-15 tires on 15-inch wheels, modifications can change how well that fitment works on the car. Wheel width changes, aftermarket wheel designs, altered ride height, and suspension work can all influence tire clearance and how the tire sits on the rim.
That is why the actual car should be inspected before choosing among GR70-15 products. A Grand Am with non-original wheels may still use the same diameter but require closer attention to width and clearance. Checking front steering travel and rear fender space can prevent fitment surprises after the tires are mounted.
What should I inspect before driving a 1973 Pontiac Grand Am on new tires?
Before driving a 1973 Pontiac Grand Am on new tires, inspect the wheels for correct diameter and condition, confirm the tires are mounted evenly, and check for adequate clearance at the front and rear. It is also wise to look over suspension, steering, and alignment condition on a collector-era car.
A fresh set of tires cannot compensate for worn components or neglected storage-related issues. Checking air pressure, lug torque, sidewall condition, and any signs of rubbing during a short test drive helps establish a safe baseline. On an older Grand Am, that first inspection often reveals whether the car is ready for regular road use.
How should GR70-15 tires on a collector 1973 Pontiac Grand Am be maintained?
GR70-15 tires on a collector 1973 Pontiac Grand Am should be kept properly inflated, inspected regularly for cracking, bulges, cuts, and uneven tread wear, and protected from long periods of heat, sunlight, and ozone exposure. Low-use collector cars can age their tires long before they wear them out.
Routine checks matter most before and after storage or before a longer drive. Rolling the car occasionally, keeping the tires clean, and watching for slow air loss can help preserve both appearance and road readiness. Any Grand Am that has been sitting should have its tires evaluated carefully before returning to regular service.
